It is easy to incorporate current transformers in metalclad circuit breakers located in a grounded tank provided with feed-throughs; the turns are then placed at the foot of each feed through; however this is not possible for circuit breakers having their housings under tension, since the low tension windings then need full tension insulation from the high tension windings; in such cases, the current transformer is kept separate from the circuit breaker. There are often occasions when it would be convenient to link the current transformer to the circuit breaker, even if the circuit breaker needs to be modified.